The MCU has given us some of the most memorable moments in the history of superhero cinema. While the Fox Marvel Universe, Christopher Nolan's Dark Knight trilogy and of course the DCEU have all done their part in defining comic book movies for the 21st century, few could deny the sheer volume of unforgettable moments that the MCU has ripped from the comic books and brought to life with the majesty and grandeur that can only come from the big screen. No comic book geek will ever forget the unmitigated joy of seeing the Avengers assemble for the first time in that one glorious tracking shot or the satisfaction of seeing Spider-Man share a screen with Iron man and Captain America unconstrained by years of tedious rights negotiations.

RELATED: 7 of the MCU’s Best Decisions (And 8 of Their Absolute Worst)

For all the visual and storytelling mastery of the MCU and its many fist pumping moments of joy there have also been moments which have left a deeply unpleasant taste in our mouths. Whether through comedic awkwardness, nerve shredding dramatic tension or the rare but inevitable moment where a scene doesn't quite hit the mark for fans, the MCU has also provided us with some uncomfortable moments. Let's take a celluloid sojourn through Marvel's back catalog to pluck out some prime examples.

16 TONY STARK'S OPEN CHEST SURGERY

Tony Pepper Arc Reactor

Tony Stark's relationship with Pepper Potts is one of the most intriguing through lines of the MCU, but this icky encounter is not among their most charming moments on screen together. When Tony Stark invents an improved version of his arc reactor he enlists Pepper to help him remove the old one, an act that requires Pepper to reach into Tony's chest cavity and have a good old rummage around.

Not only does Pepper unwittingly send Tony into cardiac arrest but her hand emerges glistening with pus plasmic discharge. The foley artist was clearly having a whale of a time here too, suffusing the scene with lots of slimy, squelching noises. Who says romance is dead, eh? It's uncomfortable to watch and curiously placed in terms of their coy flirtation, but Gwyneth Paltrow and Robert Downey Jr's chemistry make it just about bearable.

15 PETER PARKER'S PARANOID PROM RIDE

Spider Man Homecoming Michael Keaton Adrian Toomes

When you're a teenaged superhero, the only thing more terrifying than having to converse with your prom date's dad is realizing that your prom date's dad is in fact the criminal mastermind you've been fighting for days. Director Jon Watts and a tour-de-force performance from Michael Keaton capitalize on and intensify the social awkwardness by combining it with a wonderfully tense hero / villain interaction.

Toomes' restrained menace combined with Peter Parker's palpable fear and Liz's oblivious cheerfulness make for an intriguing dramatic cocktail and an atmosphere you could cut with a chainsaw. It's a moment of Hitchcockian suspense that had audiences everywhere on the edge of their seats. One of Marvel's most uncomfortable moments, to be sure, but in the very best possible way.

14 JANE FOSTER'S AWKWARD DATE

Jane Foster Darcy Richard Date

Poor Chris O'Dowd. For all the Irish thespian's boyish charm he can't seem to catch a romantic date when it comes to Hollywood movies. The awkward date in which his character Richard attempts to romance Jane Foster (who's clearly not over her lighting hurling ex) is painfully uncomfortable... And not in a good way!

Jane seems utterly indifferent to Richard's homespun appeal, burying herself behind the menu and mindlessly repeating the name of the fish course. And that's before Kat Denning's Darcy walks in with all the grace and delicacy of a runaway combine harvester and sends this car crash of a date hurtling from the avenue of bad the freeway of worse. It's a poorly written, poorly acted and ill-conceived scene that belongs on the cutting room floor.

13 DOCTOR STRANGE'S REHABILITATION

You've got to hand it to the MCU -- it's particularly adept at getting audiences to genuinely care about characters even when they act like total jerks. By the time Stephen Strange has his fateful car accident, we're already accustomed to his shameless arrogance and entitlement but that doesn't prevent us from wincing through every step of his physical rehab.

As nail-bitingly gruesome as his injuries are, the true discomfort lies in seeing his anguish and frustration as the medical science he's devoted his life to falls utterly short of saving the hands that have made him his career. With every gnashing of his teeth and each grunt of pain, Benedict Cumberbatch's performance paints a picture of a man raging against not just physical agony but the loss of his purpose in life. Seeing him lash out at his only friend, Christine, adds an extra layer of pain and tragedy.

12 DRAX'S HIGHLY INAPPROPRIATE FAMILY MEMORIES

Who would have thought that wrestling legend Dave Bautista would have revealed himself to be not just a great actor but a bona fide wizard when it comes to deadpan comedy. Drax's incredulously straight laced delivery from the first Guardians of the Galaxy is cranked right up for the sequel and while some fans felt that it diminished the brutal nature of the character, most were too caught up in the comedy to mind all that much.

His passionate recollection of the way his father would tell him every winter solstice of how he impregnated his mother is equal parts hilarious and deeply, deeply disturbing. While we may consider Drax's upbringing a Freudian nightmare, the big guys merely shrugs "You Earth people have hang ups!".

11 ERIK SELVIG TAKES A NATURIST'S TOUR OF STONE HENGE

Erik Selvig Stone Henge

If there's one thing we learned from Thor: The Dark World it's that having an Asgardian demigod tinker around with your synapses can be seriously damaging to your mental health. While this visual gag is fairly amusing as a throwaway moment, it marks the start of a long and uncomfortable spiral for the character -- from one of the greatest minds of the MCU to a puerile one-note gag that the film absolutely runs into the ground.

This was mightily irksome for those who enjoyed the first Thor. Why go to the trouble of establishing Erik Selvig as an affable and extremely smart presence in the MCU only to mishandle him so grievously later? By all means, show that an encounter with the Mind Stone takes a toll, but playing it for laughs was something of a misstep. Plus, it's not like we saw Hawkeye running around naked.

10 WHEN STEVE MET PEGGY

Steve Rogers Peggy Carter Car Awkward

One of Captain America: The First Avenger's greatest achievement is the way Chris Evan's skinny 5'4" Steve Rogers earned the love of the audience long before he became the super soldier we know and love. As earnest and winsome as Rogers is, by both the character's and Chris Evans' own admission, he's an absolute nightmare when it comes to the ladies!

His first meaningful encounter with future "best gal" Peggy Carter is a painfully awkward conversation in the back seat of a car on the way to Project Rebirth. Steve's less than subtle attempts at flirtation and abject nervousness coupled with his diminutive stature and boyish frame make it look like a 12-year old boy trying to seduce a worldly grown woman...which nobody needs to see.

9 CIVIL WAR'S CLIMACTIC BATTLE

Captain America Bucky Iron Man Fight

While many cite the airport scene of Captain America: Civil War as a standout moment, for all its spectacle, in terms of stake, its basically an extended sparring session. The final confrontation between Steve Rogers, Tony Stark and Bucky Barnes is borderline unbearable to behold. There are no fancy moves here, no superhero posturing, this is a raw and visceral fight between three people who are actually trying to harm each other.

The gloves are off and a rift has developed within the Avengers which may never heal. Check out Tony's face when Steve raises his shield for the last time. That's the face of a man who genuinely believes he's about to be murdered by his friend. We'll have to wait until Avengers: Infinity War to learn whether these two are able to patch things up, but we're not counting on a quick and easy reconciliation.

8  BRUCE BANNER GETS REAL WITH BLACK WIDOW

There's a whole lot of witty, sparkly, Whedonesque dialogue to be found in Avengers: Age of Ultron but every now and then Joss reminds us that he can cut right to the emotional quick too. Although the relationship is mostly uncomfortable, the dialogue between Natasha Romanoff and Bruce Banner in the safe house is so dramatically rich and bittersweet it belongs more to an Ibsen play than a popcorn superhero team-up movie.

In this brief exchange the essential tragedy of both characters is laid bare as Natasha flashes back to her forced sterilization and Banner flashes back to the Hulk's latest rampage. It's gut-wrenchingly difficult to watch two characters who are crazy about each other realize why they can never be together. Oh, and setting a scene in which two characters explain why they can never have a family in a child's bedroom? Ouch!

7 JUSTIN HAMMER MAKES A FOOL OF HIMSELF IN MONACO

Justin Hammer with Tony Stark and Christine Everhart in Monaco

Prior to the release of Iron Man 2 most people would argue that Sam Rockwell could do anything... other than get audiences not to like a Sam Rockwell character. In 2010 they were proven wrong! In the comics, Justin Hammer was always a low-rent tony Stark and Rockwell's performance really brings this to life, presenting us with all of the flash of Tony's billionaire playboy philanthropist motif, with absolutely none of the substance.

His sycophantic fawning over Tony in Monaco combined with his feeble attempts to assert himself over switched-on journalist Christine Everhart make for a scene that is utterly cringe worthy. Great as the acting is, the little stylistic flourishes like the abundant fake tan evident on Hammer's hands really add a layer of repugnance to the character.

6 THOR GETS A DRESSING DOWN FROM DADDY

Thor Odin Banishment

At 6'3" and over 200 lbs you'd imagine that Chris Hemsworth is a difficult actor to belittle on screen, especially when he's playing a virtually immortal demigod who can command thunder and lightning. His intimidating stature combined with his ample screen presence establish him as a cinematic force to be reckoned with in Thor's first act. His bluster and bravado are blown out of the water, however, when he shares a screen with the acting powerhouse that is Sir Anthony Hopkins.

As Odin chides his arrogant son and banishes him from Asgard the screen crackles with tension and emotion. Our hearts are in our throats as is Thor being stripped of his status and banished to Midgard to be humbled and learn humility. It's a moment worthy of King Lear, and who better to bring it to the screen than Shakespearean legend Kenneth Branagh?

5 CAPTAIN AMERICA MEETS HIS BIGGEST FAN

Coulson Captain America

Clark Gregg has a talent for understated comic delivery. It's part of what made Phil Coulson such an endearing character. For all his personal quirks he comes across as a morally sound character with a strong sense of justice so it's little wonder that he's revealed in The Avengers to be a huge Captain America fan. The scene in which Coulson reverts to a 12-year old in a middle aged man's body when discussing his "near mint" Captain America trading cards is great, but their greatest moment of interaction comes when they first meet.

Coulson's unintendedly creepy confession that he watched Cap while he was frozen in the ice is as hilarious as it is paralyzingly uncomfortable. Gregg's delivery is perfect, especially his frantic backpeddling,  but it's Chris Evans' reaction that really sells it.

4 STEVE AND SHARON'S FIRST KISS

Steve Rogers Sharon Carter Kiss

Steve Rogers has always been a little awkward around the ladies. Whether it was his stumbling and rudely uninterrupted courtship of Peggy Carter in The First Avenger or his beguilement at the hands of the far more sexually confident Natasha Romanoff in The Winter Soldier, his interactions with the fairer sex have been somewhat strained to say the least.

By the time we reached Civil War, things had improved very little. There's clearly chemistry between Steve Rogers and Agent 13 (later revealed to be Peggy's great-niece Sharon Carter) but it goes unrequited right up until their ill-timed and profoundly awkward first kiss. While in isolation, the scene is almost charming, but logically thinking about the age difference and his history with Peggy (when Steve looked pretty much the same) is a little jarring.

3 GARY NEEDS TONY

Gary's Tony Stark Tattoo

As wince inducing as Coulson's introduction to Captain America is, Iron Man has Cap beat when it comes to awkward encounters with fans. While trying to track down The Mandarin in Iron man 3, Tony Stark finds himself having to hijack a news truck's satellite connectivity. His efforts are interrupted by a camera man who just so happens to be Stark's biggest fan.

Our mounting sense of discomfort grows as the cameraman shows us his Tony Stark tattoo (which looks more like a Hispanic Scott Baio), offers to bring in a doll he made in Tony's likeness and comes to a shuddering crescendo when Stark admits "Tony needs Gary" and Gary admits a little too breathlessly that "Gary needs Tony". Happy Endings' Adam Pally wrings every drop of comedy from this insanely awkward encounter.

2 THE MANDARIN REVEALED

Trevor Slattery Mandarin

Say what you will about Shane Black, he pulled off one of the most shocking acts of misdirection in superhero movie history in Iron Man 3. After spending most of the film establishing the Mandarin as a formidable and menacing presence only to bring the whole house of cards crashing down with this shocking and divisive reveal that fans still argue over years later.

Whether you like the infamous "Trevor" twist or not, Sir Ben Kingsley is clearly having the time of his life getting to flex his little-used comedic muscle and ratcheting up the discomfort. Many fans were upset that the character of the Mandarin had been denigrated to a joke. Others were simply irked that what had been a tense sequence ended in such an anticlimax. We're just curious to see what fate has in store for Trevor in light of the Long Live The King one-shot.

1 STAR-LORD'S PELVIC SORCERY

Star Lord Gamora Pelvic Sorcery

No one can accuse Chris Pratt's Star-Lord of lacking charm... or, for that matter subtlety. In the first Guardians of the Galaxy we learn of the rogueish Peter Quill's checkered carnal history, but it's clear he's met his match in Gamora. Watching him try his moves on the daughter of Thanos is painfully uncomfortable as we know how unlikely she is to succumb to his...pelvic sorcery.

He gets an A for effort though; invoking Kevin Bacon, sharing his passion for '80s music with her and grinding away to Elvin Bishop's "Fooled Around And Fell In Love". On any number of starry-eyed waifs it might just have worked, but Quill ends up (unsurprisingly) with Gamora's knife at his throat. It's particularly painful to watch for the men in the audience; most of whom, let's face it, have tried a variation on this move with similar results.

Which moment was the most uncomfortable for you? Let us know in the comments!